NestJs custom transport for Azure Service Bus.

Description

Azure Service Bus is a fully managed enterprise message broker with message queues and publish-subscribe topics (in a namespace). Service Bus is used to decouple applications and services from each other, providing the following benefits:

• Load-balancing work across competing workers
• Safely routing and transferring data and control across service and application boundaries
• Coordinating transactional work that requires a high-degree of reliability

Installation

To start building Azure Service Bus-based microservices, first install the required packages:

$ npm i --save @azure/service-bus @niur/nestjs-service-bus

Overview

To use the Azure Service Bus strategy, pass the following options object to the createMicroservice() method:

//  main.ts

const app = await NestFactory.createMicroservice<MicroserviceOptions>(AppModule, {
  strategy: new AzureServiceBusServer({
    connectionString: 'Endpoint=sb://<Name>.servicebus.windows.net/;SharedAccessKeyName=<SharedAccessKeyName>;SharedAccessKey=<SharedAccessKey>',
    options: {}
  }),
});

Options

The Azure Service Bus strategy exposes the properties described below.

retryOptions	Retry policy options that determine the mode, number of retries, retry interval etc (read more here).
webSocketOptions	Options to configure the channelling of the AMQP connection over Web Sockets (read more here).
userAgentOptions	Options for adding user agent details to outgoing requests (read more here).

Client

@Module({
  imports: [
    AzureServiceBusModule.forRoot([
      {
        name: 'SB_CLIENT',
        connectionString: 'Endpoint=sb://<Name>.servicebus.windows.net/;SharedAccessKeyName=<SharedAccessKeyName>;SharedAccessKey=<SharedAccessKey>',
        options: {},
      },
    ]),
  ]
  ...
})

// or

@Module({
  imports: [
    AzureServiceBusModule.forRootAsync([
      {
        name: 'SB_CLIENT',
        useFactory: (configService: ConfigService) => ({
          connectionString: configService.get('connectionString'),
          options: {}
        }),
        inject: [ConfigService],
      },
    ]),
  ]
  ...
})

@Injectable()
constructor(
  @Inject('SB_CLIENT') private readonly sbClient: AzureServiceBusClientProxy,
) {}

Producer

Event-based

const pattern = {
  name: 'sample-topic', // topic name
  options: {}
}; // queue name
const data = {
  body: 'Example message'
};

this.sbClient.send(pattern, data).subscribe((response) => {
  console.log(response); // reply message
});

Message-based

const pattern = {
  name: 'sample-topic', // topic name
  options: {}
}; // queue name
const data = {
  body: 'Example message'
};
this.sbClient.emit(pattern, data);

Consumer

To access the original Azure Service Bus message use the Subscription decorator as follows:

@Subscription({
    topic: 'sample-topic',
    subscription: 'sample-subscription',
    receiveMode: 'peekLock', // or receiveAndDelete
  })
getMessages(@Payload() message: ServiceBusMessage) {
  console.log(message);
}

Options

topic	Name of the topic for the subscription we want to receive from.
subscription	Name of the subscription (under the `topic`) that we want to receive from.
receiveMode	Represents the receive mode for the receiver. (read more here).
subQueueType	Represents the sub queue that is applicable for any queue or subscription. (read more here).
maxAutoLockRenewalDurationInMs	The maximum duration in milliseconds until which the lock on the message will be renewed by the sdk automatically.
skipParsingBodyAsJson	Option to disable the client from running JSON.parse() on the message body when receiving the message.
options	Options used when subscribing to a Service Bus queue or subscription.

Stay in touch

• Author - Niurmiguel

License

Nestjs Azure Service Bus is MIT licensed.